1. Field of the Invention
The present invention relates to a radio terminal and an information reception control method in a radio communication system in which radio base stations for transmitting push type distribution information are arranged at spots.
2. Description of the Background Art
The standardization of the MMAC (Multimedia Mobile Access Communication) system as a radio communication system for providing multimedia information to a user quickly by using radio is currently in progress, and various applications utilizing a radio communication system capable of fast transmission such as this MMAC system are currently developed. For example, it is possible to consider a system in which a radio base station broadcasts information that should be notified to many users such as advertisement or emergency information, such that all radio terminals that can communicate with the radio station can receive the information.
In such a radio communication system, a radio terminal receives the information broadcasted by the radio base station. The radio terminal received the broadcasted information whenever it becomes capable of communicating with the radio base station that is broadcasting the information. Consequently, it becomes possible to receive the information from the radio base station without requiring a user to carry out an operation to receive the information. On the other hand, however, the information broadcasted by the radio base station will be received even at a location where the reception of the information is not desired by the user. As a result, there arises a problem that the radio terminal will wastefully consume its battery power and memory capacity.
An example of the conventional radio terminal will now be described with reference to FIG. 26 and FIG. 27. FIG. 26 shows an exemplary configuration of the conventional radio terminal, which is a radio terminal capable of receiving push type distribution information. Also, FIG. 27 shows an exemplary operation of the conventional radio terminal.
As shown in FIG. 26, the radio terminal 2001 includes at least a reception unit 2002 for receiving control information transmitted from the radio base station by using radio and push type distribution information transmitted from that radio base station by using radio to this radio terminal 2001 according to a request from a device other than this radio terminal 2001 (that is, without a request from this radio terminal 2001), and a reception control unit 2003 for controlling the reception unit 2002. In addition to these, the radio terminal 2001 may include an information memory device for storing the information received through the reception unit 2002 and a battery for supplying power to the radio terminal 2001.
The reception unit 2002 of the radio terminal 2001 receives the control information broadcasted from the radio base station by using radio, and the reception control unit 2003 judges whether this radio terminal 2001 itself is located within a service area or not according to whether the control information can be received or not (step S91). In the case where this radio terminal 2001 is located within a service area, the reception control unit 2003 controls the reception unit 2002 to receive the push type distribution information transmitted from the radio base station (step S92).
In the case of providing each railway station with a radio base station (having a service area that covers a range of that station) and transmitting the push type distribution information such as advertisement information or regional information related to a vicinity of that station from that radio base station, for example, the radio terminal carried around by a passenger on board will receive the push type distribution information whenever a train stops at a station or passes a station according to the above described operation. In other words, the radio terminal of a passenger who utilizes a route on which there are many stations with the radio base stations for transmitting the push type distribution information provided thereon will end up receiving a large amount of advertisement information and the like very frequently, which means a large amount of undesired information for a user of that radio terminal will be received, so that there is a problem that the handling of the radio terminal becomes poor.
Also, the radio terminal will wastefully consume its battery power and a memory capacity of its information memory device by receiving a large amount of the advertisement information and the like that is transmitted regardless of the user's preference, so that there can be cases where it becomes impossible to receive any information by the time of receiving the desired information of the user because of the shortage of a remaining battery power or an available memory capacity of the information memory device.
Moreover, the advertisement information or the like of a specific station is going to be transmitted even to the radio terminal of a passenger who has a very little possibility for actually getting on or off the train, so that it is going to be a very inefficient advertisement distribution.
Thus the conventional radio terminal in the radio communication system in which radio base stations for transmitting push type distribution information are arranged at spots will receive and store a large amount of information whenever the service area is changed as a user who is carrying around that radio terminal moves, so that there are problems that the information cannot be utilized effectively from a viewpoint of a user side, that the battery power or the memory capacity will be wasted from a viewpoint of a radio terminal side, and that the provided information will not be utilized effectively by users from a viewpoint of an information provider side.